[2][3] It is created by enumerating and classifying the crossings of an embedding of the knot in a plane.
Gauss code represents a knot with a sequence of integers.
[7] Gauss code is limited in its ability to identify knots by a few problems.
Also, the Gauss code is unable to indicate the handedness of each crossing, which is necessary to identify a knot versus its mirror.
In this modification, the positive/negative sign on the second instance of every number is chosen to represent the handedness of that crossing, rather than the over/under sign of the crossing, which is made clear in the first instance of the number.